MEDITERRANEAN SWORDFISH. STOCK ASSESSMENT MEDITERRANEAN SWORDFISH STOCK ASSESSMENT (Madrid, Spain, 3-7 September 2007) SCI-037

Background Previous assessment in 2003 (data up to 2001) MSY benchmarks were not identified

Fisheries data Gears: Longlines & Gillnets Task 1 data: 1950-2005 Size data: 1985-2005 (Main fisheries)

Catch composition Large catches of juveniles (50-70%) SWO Figure 4 Proportion of catch numbers/weight at age by year.

CPUE data Spanish longlines (1988-2005) Greek longlines (1987-2005) Italian longlines (1991-2005) Italian gillnets (1990-2001) Moroccan gillnets (1998-2006) Japanese longlines (by-catch)

Stock assessment Two assessment types Production modelling (two approaches) Age based VPAs (two approaches)

Production modeling ASPIC (long data series, assumptions about B/K were needed to achieve convergence) Current stock level about 13% lower than optimum Current F about 25% higher than optimum

ASPIC results Current F 25% higher than optimum Current stock level 13% lower than optimum

Production modeling (2nd Approach - SCRS/2007/109) (short data series, initial biomass fraction fixed, based on F derived from VPA) Current stock level 12% lower than optimum

VPA VPA-2BOX Data 1987-2005 40% reduction in spawning stock level but modest changes in the last decade XSA Stable recruitment over the past 20 years